class A {
  constructor(data) {
    this.test = data;
    console.log("a---constructor---", data);
  }
}

class B extends A {
  constructor(data) {
    super(data);
    console.log("b---constructor---", this.test);
  }
}
let oa = new A("jj");
let ob = new B("hh");
ob.test = "gg";
console.log(ob.test);

console.log(oa.test);
// console.log("oa.test---", oa.out());
